Abstract: A vertical-axis air classifier having a central product feed, a drive shaft, a tangential classifying air supply inlet located on a level with the rotor, a stationary guide vane ring arranged at a radial distance around the periphery of the rotor, a deflector-wheel rotor with one-sided bearing as well as a housing with fine material and coarse material discharge. The drive shaft, an annular-shaped fines discharge chamber arranged coaxially to the drive shaft, an annular-shaped coarse material discharge chamber arranged coaxially to the drive shaft and the bearing for the rotor are arranged on the same side and beneath the rotor to permit ease of cleaning and dismantling.